package main

import (
	"flag"
	"fmt"
	"io"
	"log"
	"os"
	"path"
	"path/filepath"
	"time"

	"github.com/go-git/go-git/v5"
	"github.com/go-git/go-git/v5/config"
)

var Error *log.Logger
var Warning *log.Logger

func init() {
	log.SetFlags(log.Ldate | log.Ltime)
	Error = log.New(io.MultiWriter(os.Stderr, os.Stdout),
		fmt.Sprintf("%sERROR:%s ", "\033[0;101m", "\033[0m"),
		log.Ldate|log.Ltime)
	Warning = log.New(io.MultiWriter(os.Stdout),
		fmt.Sprintf("%sWarning:%s ", "\033[0;93m", "\033[0m"),
		log.Ldate|log.Ltime)
}

var ROOT string

func main() {
	scanIntervalF := flag.String("interval", "2s", "scan interval")
	flag.Parse()
	log.SetFlags(log.Lmicroseconds)

	scanInterval, err := time.ParseDuration(*scanIntervalF)
	if err != nil {
		Error.Printf("error parsing SCAN_INTERVAL: %v", err)
		return
	}

	cwd, err := os.Getwd()
	if err != nil {
		Error.Printf("error getting cwd: %v", err)
		return
	}

	ROOT = path.Clean(cwd)
	ROOT, err = filepath.Abs(ROOT)
	if err != nil {
		Error.Printf("error getting absolute path for ROOT: %v", err)
		return
	}

	log.Printf("Input args parsed as:")
	log.Printf("ROOT: %s", ROOT)
	log.Printf("SCAN_INTERVAL: %.0fs", scanInterval.Seconds())

	for {
		log.Printf("Running at %s", time.Now().Format(time.RFC3339))
		doRun()
		time.Sleep(scanInterval)
	}
}

func doRun() {
	// Open the repository
	r, err := git.PlainOpen(ROOT)
	if err != nil {
		Error.Printf("Error opening repository: %v", err)
		return
	}

	// Get the worktree
	w, err := r.Worktree()
	if err != nil {
		Error.Printf("Error getting worktree: %v", err)
		return
	}

	// Check status
	status, err := w.Status()
	if err != nil {
		Error.Printf("Error getting status: %v", err)
		return
	}

	if status.IsClean() {
		log.Printf("Nothing to commit")
		return
	}
	log.Printf("Changes detected")

	// Add all changes
	err = w.AddWithOptions(&git.AddOptions{All: true})
	if err != nil {
		Error.Printf("Error adding changes: %v", err)
		return
	}
	log.Printf("Changes added to index")

	// Set identity
	err = setIdentity(r)
	if err != nil {
		Error.Printf("Error setting identity: %v", err)
		return
	}

	// Commit changes
	_, err = w.Commit("Update", &git.CommitOptions{
		Author: &config.Signature{
			Name:  "system",
			Email: "system@localhost",
		},
	})
	if err != nil {
		Error.Printf("Error committing changes: %v", err)
		return
	}
	log.Printf("Changes committed")
}

func setIdentity(r *git.Repository) error {
	cfg, err := r.Config()
	if err != nil {
		return err
	}

	cfg.User.Name = "system"
	cfg.User.Email = "system@localhost"

	return r.SetConfig(cfg)
}